I like the idea of genasi and tieflings, but they ignore the race of the characters mortal ancestors and I don't like their exact abilities. Templates would do the job, but Level Adjustment in an E6 game is a real bother. So to get my concept for characters with planetouched heiritage working, I'll be using a system similar to monster classes and racial paragon classes: You pick your base race and then take the planetouched class at at 1st level. At 1000 XP the character can take the first level in an actual class and works just like any other 2nd level character.

I'd like to hear some comments, particulary on balance, as I'm still unsure if these are too powerful or even too weak? You get a lot of fun stuff, but will always lag behind in the class features of your class.

The Basic framework for all six races is the same, based on 1 HD of monstrous humanoid:

Air
The character gains the (air) subtype in addition to any other subtypes.
+2 Dexterity.
Class Skills: Balance, Craft, Escape Artist, Jump, Listen, Move Silently.
Low-light vision.
Air Resilience: +4 to all saves against spells and effects with the [air] descriptor and air based supernatural abilities of air creatures.
Air Mastery: +1 bonus to Caster Level for all spells with the [air] descriptor.
Featherfall (Sp): The character can cast featherfall as an immediate action at will, but only at himself.

Earth
The character gains the (earth) subtype in addition to any other subtypes.
+2 Constitution.
Class Skills: Climb, Craft, Handle Animal, Jump, Sense Motive, Survival.
Darkvision 60 ft.
Earth Resilience: +4 to all saves against spells and effects with the [earth] descriptor and earth based supernatural abilities of earth creatures.
Earth Mastery: +1 bonus to Caster Level for all spells with the [earth] descriptor.
Natural Armor +2.

Fire
The character gains the (fire) subtype in addition to any other subtypes.
+2 Intelligence.
Class Skills: Bluff, Craft, Diplomacy, Listen, Sense Motive, Spot.
Low-light vision.
Fire Resilience: +4 to all saves against spells and effects with the [fire] descriptor and fire based supernatural abilities of fire creatures.
Fire Mastery: +1 bonus to Caster Level for all spells with the [fire] descriptor.
Fire Resistance 10.

Water
The character gains the (water) subtype in addition to any other subtypes.
+2 Wisdom.
Class Skills: Craft, Diplomacy, Escape Artist, Swim, Sense Motive, Tumble
Low-light vision.
Water Resilience: +4 to all saves against spells and effects with the [water] descriptor and water based supernatural abilities of water creatures.
Water Mastery: +1 bonus to Caster Level for all spells with the [water] descriptor.
Wather Breathing (Ex): The character can breath underwater indefinately.
Swim speed 30 ft.